In addition to muscle involvement, SSc patients with anti-U1RNP antibodies were younger at disease onset (120, 125, 131, 154) and presented more frequently with ILD (153, 156), PAH (123, 125), arthritis (125, 131, 153, 154) and limited skin involvement (120, 154) when compared with anti-U1RNP negative patients. Here, SNRNP70 is linked to pulmonary arterial hypertension.